Rebecca Mary had caught a spy! And, oh, how she wished that she hadn't. When she turned the key she had felt like Joan of Arc but immediately she became the most arrant little coward that ever was. She leaned against the door and trembled in every inch. She didn't know what to do with her spy now that she had caught him.

Of course, there was but one thing to do. She would have to tell old Peter Simmons and give him the key. And now that she had Frederick Befort locked in Major Martingale's office she was sorry. She had liked Frederick Befort. He was so different from any man she ever had met. He had seemed romance to her with his title, his centuries-old chÂteau, his rose-embowered country, his stories of boar hunts and kaisers and grand duchesses, and all sorts of people such as Rebecca Mary had never met on her way to and from the Lincoln school.

But Rebecca Mary had learned a lot of the little grand duchy about which she had known so little, and she knew that while there were many men in Luxembourg who had hated and feared German power there were others who would have welcomed it. Frederick Befort had told her that himself, and she had read it in a book, also. Frederick Befort had been at school in Germany, he had been born and raised almost in Germany; only the width of a river had separated him from Germany. How did they really know whether he actually had come from the Luxembourg side of the River Sure? But whether he was in sympathy with Germany or not he had stolen the secret of the great experiment which Germany wanted. That was the one thing Rebecca Mary was sure of. She had the proof of that.

And if he was a traitor he should suffer only—only—— There was Joan! As she remembered Joan, Rebecca Mary wanted to open the door and plead with Frederick Befort, make him promise to forget all about Germany, to keep faith with old Peter Simmons. If he would do that, if he could make Rebecca Mary trust him again she might—she might—— It would be too horrible for Joan to be labeled the daughter of a spy.

It was so horrible to Rebecca Mary that her hand was on the key when she heard a smothered exclamation and a thud as if a movable body had suddenly come in contact with an immovable body. Rebecca Mary cowered down beside the door and held her breath until the hall was flooded with light, and she raised her frightened eyes and saw Richard Cabot staring at her.

"What are you doing there?" He could not believe that she was listening. Rebecca Mary was not the sort of a girl who would listen at keyholes.

"H-sh!" She waved a frantic beckoning hand to him. She was so glad that it was Richard who had found her. He was so sensible, so dependable, he was Waloo's youngest bank vice-president and so was a man whom many people trusted. She had never appreciated what it meant to be sure she could trust a man before. A little glow broke through the smothering blackness which had enshrouded her as she thought of how she could trust Richard. Rebecca Mary knew that she was quite incapable of handling this situation, but she knew that Richard could handle it. She could not imagine a situation which Richard could not handle. So when Richard asked her with a compelling mixture of curiosity and determination: "What's in there?" she stammered painfully, but she told him. "A leak!"

"A leak?" he repeated stupidly for he had not heard the words Major Martingale and the others were constantly using and which had impressed themselves upon Rebecca Mary's brain. He stared at the hand which clung to the door knob. If there was a leak, although Richard did not see how that could be for there were no pipes in the office to leak, did Rebecca Mary think she could stop it by clinging to the door?

Rebecca Mary put out her other hand and clutched his arm. She had to feel him as well as see him. "I know Major Martingale has been afraid of a leak," she faltered, "and as I was coming down the stairs I saw that this door was open. You know it always has been kept locked." She went on more hurriedly after she had started as if she wished to finish her story as soon as possible. "And I saw a man at Major Martingale's desk. I did! It wasn't my imagination. I really saw him and I shut the door and—and locked it. He hasn't made a sound so he couldn't have heard me. But—but I'm frightened!" And indeed she looked frightened.

Richard frowned, but he put his hands over the fingers on his arm. "Did you see who he was?" he asked quickly in a hushed voice, almost a whisper.

She didn't answer. She simply couldn't tell him that she had, that the man who was rifling Major Martingale's desk was Frederick Befort, Count Ernach de Befort. Richard pressed her fingers gently.

"Was it Befort?" he asked in that same quick whisper.

Rebecca Mary pulled her fingers from him. "How did you know? Oh, I've told you! I've just the same as told you!" She covered her face with her hands.

Richard reached behind her and turned the key in the lock so that the door could be opened while Rebecca Mary watched him in cold despair. She couldn't understand why he did that. Surely Richard could be trusted. After Richard had unlocked the door he put his arm around Rebecca Mary and drew her out on the terrace.

"But—but——" objected Rebecca Mary, who couldn't understand why he wanted to take her away unless he wished to give Frederick Befort an opportunity to escape.

"Rebecca Mary," Richard said most irrelevantly as he drew her out with him, "you are a goose. A dear little goose," he added as if to explain to Rebecca Mary exactly what kind of a goose she was.

Rebecca Mary pulled herself away impatiently. Why should Richard waste time calling her names when there was a spy in Major Martingale's office? She stammered as she tried to tell him that there were other things for him to do now than to call her names. With a laugh Richard tightened the arm which was still around her.

"I'm going to tell you something," he said, bending his head so that he could speak directly into her pink ear. "When you locked Befort in the office you locked up the man who invented the thing we are working on. Yes, you did!" as Rebecca Mary pushed him away with a funny little strangled exclamation. "Wait a minute and listen! Yes, I know that we have all been afraid of a leak, but there hasn't been one. No, there hasn't! Listen! You know Befort comes from Luxembourg?" Rebecca Mary nodded a dazed head. She did know that, from the River Sure. "And how hot he is at the way the Germans have treated his country and his grand duchess? He was so mad that he couldn't stay neutral. He joined the French Foreign Legion and fought until he was wounded and discharged. He had invented this—this"—evidently Richard didn't know what to call the great experiment when he was talking to Rebecca Mary—"this thing," he said at last. "He had talked about it to the kaiser before he perfected it, and the kaiser wanted him to promise to give the thing to Germany. Joan and her mother had come to this country. The countess was an American, you know. She died and Befort came over for Joan. He decided he couldn't find a safer place to work out his idea than the United States. He came to Waloo and worked alone for months. Then he discovered that German agents were watching him, and he was afraid they would steal his plans. He was in the bank one day and talked to me. He never spoke of Joan so perhaps it isn't strange that I didn't connect your loan child with him. I arranged for him to meet Mr. Simmons. The thing was just in his line, and he could give Befort protection. Mr. Simmons found him a place in his factory and mechanics to help him and got the government interested for it is a big thing, a mighty big thing. Everybody came down here to finish up the job where there would be no chance of German I.W.W. interference. But you see Befort didn't have to steal the plans. He had them in the brain that invented them."

"Oh!" Rebecca Mary couldn't say another word to save her life. Her face crimsoned. She wished the terrace would open and drop her into Pekin or Shanghai. She didn't care which. How could she have made such a mistake? "But the ball!" she exclaimed suddenly, and she told Richard about the glove which Frederick Befort had turned into a ball and which was stuffed with drawings and notes for something.

"I've no doubt it was. Befort has a lot of ideas, and if he took any papers from his pocket they would be sure to be covered with drawings and figures. As for German words, you know he was practically brought up in Germany?"

"Yes," sighed Rebecca Mary. It was all so clear now that Richard had explained it to her. "No wonder you called me a goose," she said ruefully.

"A dear little goose!" When Richard was quoted he wished to be quoted exactly. His voice was very tender as he corrected Rebecca Mary.

"A goose," repeated Rebecca Mary somewhat crossly. She was in no mood for tenderness, she was too ashamed and mortified. She was almost inclined to blame Richard for the mistake she had made. If he had only told her something—anything. But if he hadn't come stumbling over the hall chair she might have accused Frederick Befort to his face. "Oh," she wailed, "I never want to see Frederick Befort again! What shall I do? I never want to see him again!"

"Don't you?" Richard seemed quite pleased to hear that she had seen enough of the romantic Luxembourg count. He had feared that Rebecca Mary might wish to see a lot more of him. "Well, you don't have to see him again," he said quickly. "I'm going to Waloo in the morning, and I'll take you with me."

"Will you?" Rebecca Mary couldn't believe there was such a simple solution to her puzzle. "Can you?" She remembered that one could not go from Riverside as one pleased.

"Sure I can." Richard spoke quite confidently. "I'd take you this minute but you've worn yourself out over this thing and you need sleep."

"I don't feel that I shall sleep until I am back in Waloo," sighed Rebecca Mary, and her lip quivered.

"Yes, you will. You'll be asleep as soon as your head touches the pillow now that you have nothing to bother over. You meet me at—is six-thirty too early? I have to go up and back before noon so I must start early."

He couldn't start too early to suit her. "There's Granny!" Rebecca Mary had almost forgotten Granny.

If Richard had thought he was going to take an early morning ride with no one but Rebecca Mary he hid his disappointment very well when he learned that they were to have company.

"Sure, there's Granny. We'll take her with us."

"And Joan?" doubtfully. Perhaps Richard would think that Joan should be left with her father.

But Richard didn't. "Joan, too. Her father will be too busy for the next twenty-four hours to look after her. He was so excited we had to send him away to-day." So that was why Frederick Befort had not been at the shop. "It has been a great day for him and unless I miss my guess there will be a greater one to-morrow." And so that was why Frederick Befort had asked her to wish him luck. Rebecca Mary blushed again as Richard went on. "Six-thirty, you know. And not a word to any one!" And lowering his voice, he whispered a few directions. He chuckled as if he were going to enjoy carrying Rebecca Mary away from Riverside. There seemed to be more in his mind than he was telling Rebecca Mary.

But Rebecca Mary was not critical nor observing. She was only grateful.

"I'll never forget your heavenly goodness!" she exclaimed as she turned to go in and tell Granny that they were to leave Riverside at six-thirty in the morning, that Granny was to have her wish and reach home before old Peter Simmons. "I'll remember it to my dying day!"

"Will you, Rebecca Mary?" Richard seemed quite pleased to hear how long he was to be remembered, and he caught her hand and pressed it before he let her go. "Will you?"